Harken XD control systems – Cunningham/downhaul

Description

Harken XD “Carbo” control systems – Cunningham/downhaul

The original equipment level originally introduced as the XD (Extra Dimension) in 2001 consisted of a 16mm single “Air” block & a 16mm single “Air” block with becket. That was “refreshed” in 2007 with those blocks being replaced by a 18mm single “Carbo” block & a 29mm single “Carbo” block (with becket rigging ability).

Whilst both of these arrangements seemed acceptable at the time & not many sailors looked for alternatives (probably because the top section of the mast was known to be on its limits anyway), neither of these system is considered adequate by todays standards. Since then things have “moved on” both in terms of materials & sailing techniques with the class introducing the composite top masts & the Standard Mk2 sail with a different cut & heavier cloth. This new sail was found to need more Cunningham/downhaul & the composite top mast, being more resilient than the aluminium top mast, was able to accept the increased compression & bending forces. As a result of this the previous 6:1 Cunningham/downhaul arrangement proved to be insufficient & 8:1 with bigger blocks, larger diameter sheaves & wider “throat” (all friction reducing features) have become the new normal. (Class rules allow five “turning points” in the Cunningham system).*

Whilst the 8:1 was primarily introduced by, & for, those using the Standard Mk2 sail many ILCA6 & ILCA4 sailors have also found the 8:1 system to be beneficial because it allows them to apply Cunningham with precision rather than just “grunting” it on…

NB The down side of 8:1 is that there is about 30% more “tail end” in the cockpit than with the 6:1 (which needs managing) but most have come to accept that as a small price to pay for the benefits of increased power.

ILCAdirect sees little point in continuing with the original systems & has thus upgraded the Cunningham/downhaul to 8:1 supplying three Harken “Carbo” 29mm “tie on” blocks as standard instead. There is some debate whether replacing one of the 29mm blocks with an 18mm “fiddle” block is better than two 29mm blocks in the traveller part of the 8:1 system so in kit form this is an option. There is a “quick rig” version which includes a hook with keeper in the primary & also, for those who find the 6:1 is adequate there is that option too.

ILCAdirect offers the Cunningham/downhaul in a number of different options as either kits or with prepared lines.

Parts in the kit are:
3 x Harken 29mm “Carbo” blocks (2 in the 6:1 option & with the “fiddle” option for one to be an 18mm “Carbo” block), 5mm Dynema D12, 3mm D12 Dynema, 4mm Yellow/white Dinghy control (with a hook as an optional addition).

Prepared lines are: Primary lines – spliced (Spliced primaries are the most effective with eye sizes to allow quick & easy line change. Secondary lines – Knotted secondary are the most effective & also allow quick & easy line change.

* ILCA class rules:
3 (e) i. The cunningham system shall consist of a maximum three control lines, “Optional” blocks or loops for purchase with a maximum of 5 “Turning Points”.

SKU Code: ILCA6013